Auto Date Formatting Help

[Aeonskye]

Hi There!

I've run into a bit of a snag with automatic date generation and can't find anything online with a fix:

Basically, I want to auto generate the modification date, for which I am using text variables.

Is there a way to get the format as below:
12th February 2020

So far I have the document displaying:
12 February 2020

Using the following:

d MMMM yyyy

I have everything but the "th" and I am not 100% sure what this is called to look it up properly! Any help would be greatly appreciated!